According to the people from MagicDraw, the following is an error in the XMI produced by BOUML. IN the below, the ownedRule is only supposed to appear within a Namespace, not a Property. I'm not 100% sure what this means but presumably that the outer ownedAttribute's xmi:type should be "uml:Namespace" instead of "uml:Property". This would need to be checked against the OMG XMI 2.x specification.

This problem isn't causing an immediate problem, because the MagicDraw importer is smart enough to get past the error (it just rejects the ownedRules), but I guess it would be good to fix in the long run.

Other than this one error, the BOUML XMI for my model, with about 150 classes imports fine into MagicDraw, and in fact they have an error in their own XMI importer that they need to fix.

Lets look at http://www.omg.org/spec/UML/20110701/Superstructure.xmi "OwnedRule" is defined at line: 8019 and it is within "Namespace" element which is defined starting at line 7978. <packagedElement xmi:type="uml:Class" xmi:id="Classes-Kernel-Namespace" name="Namespace" isAbstract="true">

So ownedRule may be contained only in Namespace.

In the wrong sample ownedRule is serialized inside property which is not namespace, and thus can not contain ownedRule.

Maybe it makes sense to talk to BOUML people?

I personally don't know who is right, and don't have time to study this detail, but I hope it's useful for you with BOUML.